Photographic layer and process of producing same



Mamh 1940- w. P. M. J. ROBIJNS' PHOTOGRAPHIC LAYER AND PROCES$ 0F PRODUCING SAME Filed April 2'7, 1937 or inorganic nature.

the light-sensitive layer large quantities of gran- Patented Mar. 5, 1940 UNITED STATES PATENT OFFICE PHOTOGRAPHIC LAYER AND PROCESS OF PRODUCING SAME Willem Pieter Maria Jose! Robijns, Mortsel, Belgium, assignor to Gevaert Photo-Producten, N. V., Dude-God, Antwerp, Belgium Application April 27,1931, Serial No. 139,185

In Austria May 2, 1936 1 8 Claims.

dimensional object reproduced by the image. As

a rule this eil'ect is styled stereoscopic or plastic".

My invention comprises both the photographic article such as a light-sensitive layer arranged on a suitable carrier, with the aid of which such images can be produced, and the process of making this article. I

- As is well known to those skilled in the art, light-sensitive papers of velvet-like appearance, which display a certain plastic effect, are obtained by fixing on the carrier (the paper) vegetable or animal fibres by means of a suitable binder and arranging the light-sensitive layer,

on this carrier, after the binder has dried down completely.

I obtain light-sensitive layers imparting to the images produced with their aid a great plasticity by incorporating in the emulsion forming the light-sensitive layer fine grains capable of agglomerating in the layer to form comparatively coarse aggregates, or I may introduce both fine and coarse grains. I have found granules of the order of those passing through a sieve with about 20 meshes per linear centimetre to be most suitable for my purpose.

The agglomerated granules i'mpart to the lightsensitive layer a surface which reflects the light rays repeatedly in succession, whereby a plastic effect is produced. The image produced in a layer according to this invention is not confined to the two dimensions of a plane, but the third dimension is utilized also in the formation of the image.

The granular substance to be {incorporated in the light-sensitive layer maybe of an organic Since in the production of ules are used without paying regard to their specific gravity, which may be high, the granules should possess a low covering power. I therefore'prefer' organic substances such as artificial resin, or inorganic products such as silicates, for instance ground glass. Preferably the covering power of thegranular matter should be lower than that of barium sulfate.

A light-sensitive layer according to my inventionmay consist for instance of a photographic silverhalide emulsion, in which are distributed granules resulting from the agglomeration of fine or fine and coarser particles of the nature and dimensions here above described, this layer being 5 arranged on a suitable carrier, for instance on paper.

In the drawing affixed to this specification and forming part thereof an article embodyingmy invention is illustrated in a purely diagrammat- 1 ic'al manner and on a greatly exaggerated scale by way of example in cross section.

I is the carrier, 2 is the photographic layer containing silver halide, 3 are comparatively large sized granules embedded in this layer which are combined by agglomeration with small sized granules 4 and are so arranged in the photographic layer as to render its surface rough and uneven.

If a. photographic image is produced on this layer by exposure to light in the camera or under a negative and subsequent development, this image will impart to the onlooker the impression of having before him not a plane image, but the article itself which is reproduced by the image.

Various changes may be made in the details disclosed in the foregoing specification without departing from the invention or sacrificing the advantages thereof.

I claim:

1. As a new article of manufacture, a lightsensitive layer comprising a photographic silver halide emulsion and a plurality of agglomerates of granules of different sizes distributed in this emulsion and rendering the surface of the layer uneven, said agglomerates being of the order of granules passing through a sieve of 20 meshes per linear centimetre.

2. As a new article of manufacture, a lightsensitive layer comprising a photographic silver 40 halide emulsion and a plurality of granules distributed inthis emulsion and rendering the surface of the layer uneven, said granules being of the order of granules passing through a sieve of 20 meshes per linear centimetre, some of the 45 granules being agglomerates of coarse and fine grains.

3. As a new article of manufacture, a lightsensitive layer comprising a photographic silver halide emulsion and a plurality of agglomerates -of organic matter distributed in this emulsion 4. As a new article of manufacture, a light-'- sensitive layer comprising a photographic silver halide emulsion and a plurality of aggiomerates of inorganic matter distributed in thisemulsion and rendering the surface of the layer uneven, said agglomerates being of the order of granules passing through a sieve of 20 meshes per linear centimetre.

5. The method of producing a photographic article which comprises distributing in a photographic emulsion, a plurality of granules'which are agglomerates of the order of granules passing through a sieve of 20 meshes per linear centimetre in such manner as to produce a light-sensitive layer having an uneven surface and de-.

positing the emulsion containing these agglomerates on'a carrier. I

6. As an article of manufacture, a light-sensitive layer comprising a photographic silver halide emulsion and a plurality of granules of at least two widely diflerent sizes forming agglomerates 

